"The average data center runs at 1.6 to 1.8 power usage effectiveness (PUE) — the ratio of the power used by a data center to the power delivered to it — while Facebook’s facility runs between 1.05 and 1.10 PUE over the course of the year, close to the ideal 1-to-1 ratio.

“We want to be the most effective stewards of the electrons we consume. If we pay for 100 megawatts of power we want to use 100 megawatts of power,” Patchett says. “The average house is between 2 and 3 PUE. That’s twice the amount of energy you actually have to assume. What if every home was the same efficient steward that we are?”"

[The format change means I captured this via Chrome/Blog This rather than IE/Windows Live Writer]